A vehicle-following control in which an own vehicle travels following a preceding vehicle traveling in the same lane as the own vehicle among the preceding vehicles traveling in front of the own vehicle is known as an example of a vehicle traveling support control. It is important that such a vehicle-following control accurately selects the vehicle traveling in the same lane as the own vehicle among the preceding vehicles detected by a sensor, a camera, and the like. Therefore, calculating a future travel route of the own vehicle, and setting the preceding vehicle present on the future travel route as the target of the vehicle-following control has been performed conventionally. Further, various methods for calculating the future travel route of the own vehicle have been proposed (for example, refer to PTL 1). PTL 1 discloses that a traveling locus of the preceding vehicle traveling in front of the own vehicle is stored, and the stored traveling locus is used to calculate the future travel route of the own vehicle.